The present invention relates to an apparatus and method for generating waves in a body of water, and more particularly to an apparatus and method for generating such waves which includes means for effectively dissipating a portion of the wave energy so generated.
There are many types of artificial wave generation devices which are presently in use. Such devices are finding increasing use in recreational and aquatic parks to create waves in large swimming pools and the like. The dam break method pumps large quantities of water into a tank above the level of water in a pool. The water is then released suddenly to produce a surging wave along the length of the pool. Pneumatic wave generation devices operate by alternately blowing and venting an air plenum which is partially submerged in a tank of water. An opening at the bottom of the plenum, which is in communication with the water in the pool, allows the water to flow back and forth to produce waves in the pool. Another mechanical type of wave maker utilizes a wedge shaped plunger which is oscillated vertically to produce waves.
A wave generation device which has gained popularity in recent years is a hinged wave flap generator. In this device, which is explained in detail in Biewer, U.S. Pat. No. 4,062,192, a vertically-oriented wave flap hinged at its base at the bottom of a body of water is oscillated at the top by a hydraulic device. The period of the wave formed corresponds to the period of oscillation of the flap, and the wave height is determined by the amount the wave flap is displaced during each cycle. A somewhat similar device for creating waves, called a bulkhead wave generator, operates by moving a bulkhead, wave board, or wave flap back and forth beneath the water. Again, the period of oscillation and length of displacement affect the size and intensity of the waves which are formed.
One problem associated with hinged wave flap generators and bulkhead wave generators in the past has been the problem of dissipating the wave energy created by the return stroke of the wave flap. As these devices are located very near one end of a pool or the like, a large amount of energy must be dissipated in a relatively confined space. The Biewer patent teaches the use of a nonbuoyant material such as stainless steel shavings positioned behind the wave flap near the end of a pool or the like to absorb and dissipate the wave energy from the return stroke. Others have utilized collections of absorbent foam materials, corrugated plastic field tile, and the like positioned behind the wave flap in an attempt to absorb and dissipate the wave energy. None of the above solutions has been very satisfactory. Either the energy from the water waves is not adequately dissipated and the end wall of the wave pool or the like is subjected to periodic potentially damaging vibrations or the energy dissipating material, which is repeatedly subjected to strong forces, dislodges or breaks up.
Accordingly, there is still a need in this art to provide a method and device which will efficiently dissipate the wave energy which results from the return stroke of a wave flap or the like in a wave generation device.